Abstract

Microphotoluminescence studies of AlGaO-based asymmetric waveguide microdisk structures incorporating a single sheet of self-organizedInAsquantum dots(QD) under photoexcitation are performed. The authors have observed a strong redshift and broadening of the QD optical transition energy at high excitation densities due to excitation-density-induced overheating and many-particle effects and monitored the impact of these effects on the whispering gallery modes (WGMs) in spontaneous and stimulated emission regimes. They have observed strongly nonmonotonic dependencies of the linewidth and intensity of the WGMs with excitation density increase and underline possible reasons for the observed behavior.

Received 03 July 2007Accepted 27 August 2007Published online 18 September 2007

Acknowledgments:

This work was supported in different parts by the EU Projects “SANDiE” (Contract No. NMP4-CT-2004-500101), Russian Foundation for Basic Research (05-02-16922-a), NATO Science for Peace (SfP.982735), the Program of Fundamental Studies of the Presidium of RAS “Quantum Nanostructures,” and grant of St. Petersburg Scientific Center of RAS. One of the authors (S.A.B.) gratefully acknowledges financial support from DFG (SFB296).